Can Static Destroy Electronics?

Try it and see. Those grounds are all the same. That is, the ground on the phono stage is chassis ground, whether its the ground screw used or any other screw that goes into the chassis. Same for the amp. These all go to ground. 

Where you can run into problems is they all go to ground but not the same path. If everything were perfect, zero resistance across the board, then it wouldn't matter. Where there is even a small differential though, then some current goes one way, some another, and this is where the hum comes in. That is why the recommendation to have everything on one circuit. This ensures every path to ground is the same and so tends to be very quiet. 

But people can often times get away with violating this rule and not notice problems. Better lucky than good, eh? 

Phono stages are the highest gain and greatest EQ in all of audio. Orders of magnitude greater. The same exact imperfections that will never show up with other components can have you at the end of your wits with phono. To the point where even when you understand everything going on it still sometimes comes down to try it and see.

Yes for sure BEWARE STATIC!!!

But can the chassis of a component WITHOUT a ground pin on its plug actually act as a ground? I would expect that the chassis has continuity to the ground pin of the plug, which then plugs into the grounded socket, thus completing the path to the actual ground.

There is an article on the grounding of the Technics SL-1200 and you can find it here -  Internal Grounding » Technics 1200 Parts, Technics 1210 Parts, Technics Repair Turntable Repair, Mods Modifications, Pro Audio Parts, Accessories, and Repairs, Toronto, Ontario, Canada (technics1200s.com).  It appears that the newer units are no longer internally grounded.  Its not a safety issue, many electrical equipment such as plastic housing power drills are only 2-wire; from a ground safety - they are intrinsically safe and the reputable ones are UL approved.  But even if the motor was grounded, unless the metal tonearm is somehow connected, grounding the motor is not going to help.

Current Theory: I believe the ground wire coming out of theTechnics 1200 is attached to the tonearm. When the ESD happened upon lifting the tonearm, it makes sense it would travel through that ground wire and arrive at the phono preamp where it was connected, as the next stop on its journey for ground.


Since the preamp does not have a 3rd prong (the ground prong), the electrostatic discharge didn't have a safe path to ground, so instead of bypassing the sensitive electronics, it pulsed through them, breaking something along the way. 


I've attached my TT ground to a screw on the chassis of my fully earth-grounded amplifier, which will hopefully send any electrical discharges down a safe path to ground. As an added benefit, I have discovered an all-new blackness to my vinyl background I didn't even know possible. 


Hopefully those who are more knowledgeable about electrical theory can confirm or deny the above hypothesis!